I found three references, well probably just two but still . . . well . . . wait. One reference is a Free Woman. . . . In any event, yes, there is a reference to a girl wearing a black ribbon.
Her blond hair was lifted from the sides and back of her head by a comb of bone and leather, like an inverted isosceles triangle, the comb fastened by a tiny black ribbon about her neck and another such ribbon about her forehead.
Marauders of Gor    Book 9    Page 35
She wore a black, tight, off-the-shoulder bodice and a short, black, silk skirt, decorated with red thread and ruffles, and stiffened with crinoline. A black ribbon choker was placed behind the steel collar on her throat. A red ribbon, matching the decorations on her skirt, was in her hair. She had not been permitted stockings or footwear.
Savages of Gor    Book 17    Page 115
"Get your clothes off," said the auctioneer.
Swiftly the girls complied. Ginger removed even the beaded cuff on her left ankle. Evelyn removed even the black-ribbon choker on her throat. They were then stark naked. Both, I saw, had been well branded.
Savages of Gor    Book 17    Pages 127 - 128
